TEM Method
Early-stage tumors in the rectum near the anus tha...
The large intestine, called the colon, is located between the last part of the small intestine and the anus. They are approximately 1.5 meters long and have the shape of an "M".
It consists of a vertical part that goes up, followed by a horizontal part and then another vertical part that goes down. Each part has a name. Cancers that arise from the cells that line the inner surface of these intestinal parts and are called epithelium are called "Colon or Large Intestine Cancers".
When we look at the distribution of colorectal cancers, 25% are on the right side and 15% are horizontal.
In the section, 5% is located in the left side descending section, 25% is in the lower part called the sigmoid colon, which takes an "S" shape, 10% is in the rectosigmoid section where the sigmoid and the rectum meet, and 20% is located in the rectum, which is located at the bottom of the large intestine.
Along with rectal cancers, it ranks 3rd after bronchial and prostate cancer in men and 2nd after breast cancer in women. Generally, 90% of it occurs after the age of 50. The most common age group is the 6th and 7th decades. (Ages 60-70) The cause is not fully known, as in many other cancers.
Risk factors that play a role in cancer development; Factors such as age, diet, personal history, family history, and inflammatory bowel diseases can be considered.
Since the risk increases after the age of 50, it would be wise to start screening tests after the age of 50.
While colon cancer is more common in developed countries, it is less common in Asia and Africa. It has been observed that especially high-calorie foods such as sugar, carbohydrates and foods such as red meat and animal fat are effective in colon cancer. However, this risk does not increase in foods such as diet rich in oleic acid (olive oil, fish oil, etc.).
There is information that oil has a toxic effect on the colon mucosa, while plant fibers are protective.
Consuming plant fibers that leave plenty of pulp shortens the contact time of carcinogenic substances with the colon mucosa, and at the same time reduces the negative impact on the mucosa by increasing the volume of feces and causing the dilution of harmful substances.
It is stated that the use of calcium, selenium, vitamins A, C, E and carotenoids reduces the risk of colon cancer.
The risk of colon cancer increases in people who are obese and lead sedentary lives.
Most colon cancers arise from polypoid formations, adenomas, in the intestine. These adenomas or adenomas turn into cancer in about 10 years. This is called “adenoma-carcinoma sequence”.
Some of the colon cancers also occur hereditarily.
Colon cancers grow for a long time without any symptoms. Since cancers, especially those located on the left side, are constrictive, one day the patient will face intestinal obstruction. In cancers located in the sigmoid colon, first heavy bleeding is observed, and then from time to time a small amount of bleeding is observed in the stool. Most of the time, hemorrhoids are treated incorrectly, considering them to be hemorrhoids.
In right-sided colon cancers, bleeding is less noticeable because it is mixed with stool. ANEMIA often occurs due to this hidden bleeding.
Stool change is a finding that should be taken seriously in colon cancers. Due to the liquid content of the large intestine, obstruction is only seen in very large tumors. The majority of patients have mild diarrhea. Anemia due to chronic blood loss; It causes fatigue, weakness, deterioration in general condition and weight loss. Suspicious pain in the lower right side of the abdomen and a mass may be detected in this area during examination.
The left colon is narrower and its contents are more solid, so obstruction is more common. Constipation occurs at first, but diarrhea occurs due to fluid accumulation above the obstruction.
A cycle of constipation and diarrhea is a significant finding. The patient feels unwell and loses weight due to abdominal tension, colicky pain, and mucus-bloody stools.
Colonoscopy should be performed for every anal bleeding, especially in people over the age of 40. About 10% of such patients are diagnosed with cancer.
Considering that the 5-year survival rate in colorectal cancer is 90% in the early stages and decreases to 5% in the advanced stages, it can be seen how important early diagnosis and screening programs are. Average risk and high risk groups are determined and different screening programs - protocols are recommended for each group.
There are different applications in treatment, such as first surgery, then chemotherapy, or first chemotherapy, then surgery, then chemotherapy again. The appropriate treatment modality is decided according to the location of the cancer, its stage, and whether it has caused distant metastasis, that is, spread.
The main goal of surgery is to remove the cancerous colon section, the mesocolon, which includes its lymphatic drainage, and the surrounding organs and structures affected by cancer. Depending on the location of the cancer, all the mesocolon up to the main root from which the blood vessels emerge should be removed together. This method, called C M E (complete mesocolic excision), has been routinely performed by surgeons dealing with colorectal surgery in recent years.
After the removal process, continuity is achieved by connecting the intact and clean bowel ends with a stapler or hand anastomosis. Such surgeries can be performed openly or laparoscopically or roboticly, depending on the surgeon's experience.